ABSTRACT
BACKGROUND: Sinus pericranii (SP) is a rare venous anomaly involving an abnormal connection of the intracranial dural sinuses with the extracranial veins. Magnetic resonance (MR) imaging (MRI) with MR venography can detect the typically congested intra- and extracranial venous components of SP. CLINICAL PRESENTATION: We report a rare case of lateral SP associated with the superior sagittal sinus, which might had already developed almost total thrombosis of the SP at the first MRI. As this patient had not presented with classical manifestations of SP on clinical or neuroradiological findings, the initial diagnosis of SP was difficult. Repeated MRI revealed dynamic morphological changes associated with reperfusion of the thrombosed SP via the cortical vein. CONCLUSION: MR venography combined with gadolinium enhancement was useful for diagnosis of the SP with an extremely slow flow status.