On geometric modeling of the human intracranial venous system.

We describe a process aiming to construct a 3-D geometric model of the human normal intracranial venous system from MRA data. An analysis of geometric properties of the intracranial veins and sinuses results in proposing three models: circular, elliptic, and free-shape. We formulate a rule based on which a suitable geometric venous model can be selected. The cross-sectional shape of different parts of dural venous sinuses is found to be better approximated by ellipses and free shapes, while for veins the circular and elliptic models are comparable. An analysis of using splines for radii smoothing is also provided. The approach is useful for building venous models in education and clinical applications.