Tipping point in middle meningeal artery embolization: a cost-effectiveness and algorithm-based analysis

Chronic subdural hematoma (cSDH) is one of the most common diseases treated by neurosurgeons. While surgical evacuation has been the traditional way to address symptomatic lesions, there is expanding evidence of the beneficial use of middle meningeal artery (MMA) embolization as a treatment or as an adjunct for cSDH. With the current strain on healthcare resources, physicians must balance providing the best care for patients and making cost-conscious decisions. Therefore, the aim of this study was to compare the cost of surgery alone versus surgery plus MMA embolization for treatment of cSDH, and to calculate an institutional tipping point for cost benefit.

This is a retrospective study of patients with symptomatic cSDH requiring surgical intervention at a single institution from May 2019 to December 2022. The patients were concurrently enrolled in a prospective randomized controlled trial. To compare the cost of surgical treatment alone versus surgical treatment plus MMA embolization, all charges related to cSDH treatment from admission to the last follow-up were categorized (procedure, radiology, pharmacy, intensive care unit bed, laboratory, floor bed, and other) and assessed. The institutional tipping point (point at which it becomes financially beneficial to add MMA embolization to surgical evacuation during the same admission) was calculated to help guide decision-making.

Forty-one patients (28 male, mean age 67.9 years) were included in the analysis, and were previously randomized to surgical intervention only (n = 21) or surgical intervention plus MMA embolization (n = 20). The groups were comparable in terms of demographic and cSDH characteristics. The overall mean cost for the index admission was lower in the surgery only group (US$158,320 vs $235,263; p = 0.037). This was also true for all categories of charges. Throughout the duration of the study there were 27 admissions in the surgery only group and 20 admissions in the surgery plus MMA embolization group (p = 0.0052). When analyzing costs per patient instead of per admission, no differences were observed between treatment groups for any of the categories. Likewise, the overall mean costs related to the care of patients in either treatment group showed no statistical difference ($203,554 vs $235,263; p = 0.25). Consequently, the institutional tipping point for the addition of MMA embolization was 20.8%.

MMA embolization can be considered as an adjunct to surgery in the treatment of symptomatic cSDH, decreasing the overall cost by lowering rates of readmission and repeat intervention. The tipping point formula used in this study is versatile and adaptable. It can be a useful guide to determine appropriate treatment options for patients with symptomatic cSDH according to institutional or national standards.