Accuracy of non-contrast brain CT in pre-embolization evaluation of the middle meningeal artery.

PURPOSE Chronic subdural hematoma (cSDH) is typically diagnosed on non-contrast brain CT. Embolization of the middle meningeal artery (MMA) has become an increasingly adopted treatment, but pre-procedural assessment of MMA anatomy remains essential because anatomical variations may affect procedural safety. This study evaluated whether three-dimensional (3D) reconstructions from routine non-contrast CT can depict MMA anatomy compared with digital subtraction angiography (DSA), the reference standard.

MATERIALS AND METHODS In this retrospective study, 76 patients (91 MMAs) who underwent both non-contrast CT and DSA were analyzed. The anterior, posterior, and middle branches were assessed. Branch dominance was categorized as Type I (anterior), Type II (posterior), or Type III (mixed), and posterior branch origin as proximal (A), intermediate (B), or distal (C). The Extended-Adachi classification was used for overall anatomical patterns. The foramen spinosum (FS) and MMA tortuosity were also evaluated. Concordance rates between CT and DSA were calculated.

RESULTS On CT, the anterior, posterior, and middle branches were visible in 100%, 94.5%, and 96.7% of cases, respectively. CT-DSA concordance was high for branch identification (91.1%, 85.7%, and 78.0%) and lower for dominance (45.5%) and posterior branch origin (39.3%). Absence of the FS on CT was strongly associated with anatomical variants (3/4 cases).

CONCLUSION 3D reconstructions from non-contrast CT allow reliable visualization of the main MMA branches. Assessment of the FS may provide an additional indirect indicator of anatomical variation, although this finding requires confirmation in larger studies. Pre-procedural recognition of MMA variants may help optimize procedural planning and reduce the risk of non-target embolization.