Cortical vein

Fig. 18.7a,b. Isolated cortical vein thrombosis in a 16 y old female presenting with focal epileptic seizures, a Axial GE (T2 ) images show a hypointense signal along the course of a cortical vein (arrows) which was also seen as a hyperdense structure on CT (not shown), b Axial DWI shows small areas of restricted diffusion in the corresponding brain parenchyma... 

Boukobza, M., et al., MR imaging features of isolated cortical vein thrombosis diagnosis and follow-up. AJNR Am J Neuroradiol, 2009. 30(2) p. 344-348. 

Classification is mainly based on venous drainage with those DAVMs draining into a cortical vein classified as dangerous. In many patients CT and/or MRl can already confirm the diagnosis of a DAVM. 

Transsecting the hippocampus at this level one will encounter small hippocampal veins which are easily coagulated and divided. There will also be from one to three larger cortical veins coursing to veins in the collateral sulcus and thence to the medial cortical vein. These need to be eliminated... 

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