In Vivo Demonstration of Traumatic Rupture of the Bridging Veins in Abusive Head Trauma

OBJECTIVE: In victims of abusive head trauma, bridging vein thrombosis is a common finding on magnetic resonance imaging. We aimed to evaluate the utility of high-resolution coronal susceptibility-weighted imaging (SWI) in depicting bridging vein thrombosis as well as to verify the morphology of the bridging vein thrombosis on axial SWI. We additionally analyzed the correlations between bridging vein thrombosis or bridging vein deformation and other magnetic resonance imaging findings that often occur in association with abusive head trauma. METHODS: Seventeen patients with abusive head trauma were retrospectively evaluated for the presence of thrombosis on axial SWI. The affected veins were localized on coronal SWI, and the strength of association between the presence of bridging vein thrombosis on axial versus high-resolution coronal SWI was determined. RESULTS: Of 11 patients identified with thrombosis on axial SWI, high-resolution coronal SWI verified bridging vein thrombosis in four individuals (36%). The previously reported tadpole sign on axial images did not predict bridging vein thrombosis on coronal SWI (odds ratio = 0.3 [0.02, 5.011, P = 0.538). Volumetric coronal SWI disclosed additional irregularities of the bridging vein walls which was associated with the presence of subdural hematoma on magnetic resonance imaging (P = 0.03), suggesting traumatic injury. CONCLUSION: coronal SWI confirmed thrombosis of the bridging veins only in a minority of cases. Diffusely irregular contours of the veins observed on high-resolution coronal SWI was a major finding in our study. Disruption of the normal anatomy of the bridging veins in abusive head trauma further supports the traumatic nature of the disease.